Mt. Wyder et al., Influence of two different propionibacterial cultures on the characteristics of Swiss-type cheese with regard to aspartate metabolism, MILCHWISSEN, 56(2), 2001, pp. 78-81
Propionibacteria are used in the Swiss cheese industry to achieve the chara
cteristic eyes and nutty flavour of Emmental or Swiss-type cheese. The aim
of the present work was to further understand the influence of 2 different
propionibacterial cultures, Prop 96 and P-culture, on the characteristics o
f Emmental cheeses. The P-culture has a strong ability to metabolise aspart
ate. Biochemical, microbiological and sensory analysis clearly revealed tha
t the cultures lead to completely different Emmental cheeses. Compared to P
rop 96, the P-culture yielded higher propionibacterial counts and showed an
increased utilisation of lactate and aspartate with resulting higher conte
nts of free short chain acids and carbon dioxide. As a result, the flavour
of the concerned cheeses was more intense and the number and size of eyes,
as well as height of the cheeses were greater. It can be concluded that the
ability of propionibacteria to utilise aspartate must definitely be taken
into consideration for the selection of cultures. Even though excessive asp
artase activity has hidden dangers such as late fermentation, a moderate ac
tivity may influence the properties of Emmental cheeses positively and acce
lerate ripening. The aspartase activity is most probably an important indic
ator for the growth rate of propionibacteria in Emmental cheese.